SINGAPORE (Reuters) - The Singapore index was on course for a third straight session of losses on Friday, but found some support from gains in Olam International after Temasek Holdings said it would buy all minority shares in the commodity trading firm.

Olam shares soared as much as 12 per cent to a 22-month high of $2.23 - the price at which a Temasek-led group offered to buy each share held by minority shareholders.

"For shareholders who have already enjoyed strong gains or are medium-term shareholders, they can consider taking up the offer," said OCBC analysts in a research note, adding that Olam's share price had risen 40 per cent since late January.

The robust gains in Olam helped slow the decline in the benchmark Straits Times Index, which eased 0.4 per cent to 3,067.99 points by midday, compared with an over 1 per cent drop in the MSCI's broadest index of Asia-Pacific shares outside Japan.

The benchmark index looks set to post a 2.2 per cent decline this week, its deepest weekly fall in seven.

In other stocks, Golden Agri-Resources was headed for a 3.3 per cent loss this week, its first weekly fall in six.